1. Field of the Invention
This invention relates to improvements in connectors comprising any of various jacks such as so-called pin jacks or single-headed jacks.
2. Description of the Related Art
Two types of connectors attached to printed circuit boards for connecting mainly various types of electronic device to electrical and electronic circuit components on the printed circuit board are conventionally known, namely the board plug-in type and the surface mounting type. The former type is configured such that connector terminals are plugged into through holes in the printed circuit board, while the latter type is configured such that the connector is mounted on the surface of the printed circuit board.
Both of these types of connectors require soldering for securing them to the board and for electrically connecting the circuit components on the board. With the board plug-in type of connector, because it must undergo the processes of flux coating, reflow treatment, solder dipping, and washing, it is necessary to consider flux resistance, reflow heat resistance, solder heat resistance, chemical resistance, and solder wettability. With the surface mounting type of connector, on the other hand, because the processes of reflow treatment and washing must be undergone, it is necessary to consider reflow heat resistance, chemical resistance, and solder wettability.
In recent years, however, in order to avoid such problems as the destruction of the natural environment on a global scale, and the depletion of natural resources, the rapid transition from so-called use and throw away economics to so-called recycle economics has become a top priority. There is a high probability that in the near future manufacturers will be obligated to implement product recycling operations wherein it is presumed that, after various types of electrical products have once passed through the hands of a consumer, the original electrical equipment manufacturer will take those products back, disassemble them into their many components, and sort those components into reusable components which will be used in new products and unreusable components which will be disposed of.
Both of the connectors described earlier are configured such that they are securely attached to a board by soldering. In the case of the board plug-in type connector, in particular, the strength with which it is secured by soldering is comparatively great in view of the attachment structure thereof, wherefore it is impossible in practice to separate the connector and the printed circuit board without damaging both the connector and the printed circuit board. In the case of the surface mounting type of connector, on the other hand, the strength wherewith it is secured by soldering is weak, so the structure is made such that, when used, the area surrounding the points of attachment of both members is reinforced so that the pattern on the printed circuit board does not peel away, wherefore, as in the case described above, it is impossible in practice to separate the connector from the printed circuit board without damaging the connector and the board.
With the current level of technology, moreover, it is very difficult to manufacture connectors or printed circuit boards of materials that are highly resistant to heat, wherefore alloys that have too high a melting point cannot be used for the solder. Hence there is no alternative but to use solder made of alloys of tin and lead considered to have comparatively low melting point while fully cognizant of the adverse effects which lead has on the environment. Furthermore, so long as solder is used for securely attaching the connector to the printed circuit board, other problems arise because of the various processes required in soldering operations which are unfavorable to the natural environment, namely flux coating, reflow treatment, solder dipping, and washing, etc.
Accordingly, an object of the present invention is to provide a connector which can be attached to a board with adequate attachment strength but without requiring soldering, and which can be easily removed from the board without causing damage.